Since the Answer for Both 23 − 17 and 26

Multiple Choice

Since the answer for both 23 − 17 and 26 − 20 is 6, the logic behind equal addition subtraction algorithm is:

A) adding the same number to both the subtrahend and minuend changes the answer.
B) increasing the subtrahend and decreasing the minuend does not change the answer.
C) subtracting any two numbers will give the same answer.
D) adding or subtracting the same number to both subtrahend and minuend keeps the difference between two numbers the same.